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<pre><span class="sourceLineNo">001</span><a name="line.1"></a>
<span class="sourceLineNo">002</span>/*<a name="line.2"></a>
<span class="sourceLineNo">003</span> * Copyright (C) 2011 Archie L. Cobbs. All rights reserved.<a name="line.3"></a>
<span class="sourceLineNo">004</span> *<a name="line.4"></a>
<span class="sourceLineNo">005</span> * $Id: AsyncOutputStream.html 973 2015-04-22 14:58:55Z archie.cobbs $<a name="line.5"></a>
<span class="sourceLineNo">006</span> */<a name="line.6"></a>
<span class="sourceLineNo">007</span><a name="line.7"></a>
<span class="sourceLineNo">008</span>package org.dellroad.stuff.io;<a name="line.8"></a>
<span class="sourceLineNo">009</span><a name="line.9"></a>
<span class="sourceLineNo">010</span>import java.io.FilterOutputStream;<a name="line.10"></a>
<span class="sourceLineNo">011</span>import java.io.IOException;<a name="line.11"></a>
<span class="sourceLineNo">012</span>import java.io.OutputStream;<a name="line.12"></a>
<span class="sourceLineNo">013</span>import java.util.concurrent.atomic.AtomicInteger;<a name="line.13"></a>
<span class="sourceLineNo">014</span><a name="line.14"></a>
<span class="sourceLineNo">015</span>import org.dellroad.stuff.java.CheckedExceptionWrapper;<a name="line.15"></a>
<span class="sourceLineNo">016</span>import org.dellroad.stuff.java.Predicate;<a name="line.16"></a>
<span class="sourceLineNo">017</span>import org.dellroad.stuff.java.TimedWait;<a name="line.17"></a>
<span class="sourceLineNo">018</span>import org.slf4j.Logger;<a name="line.18"></a>
<span class="sourceLineNo">019</span>import org.slf4j.LoggerFactory;<a name="line.19"></a>
<span class="sourceLineNo">020</span><a name="line.20"></a>
<span class="sourceLineNo">021</span>/**<a name="line.21"></a>
<span class="sourceLineNo">022</span> * An {@link OutputStream} that performs writes using a background thread, so that<a name="line.22"></a>
<span class="sourceLineNo">023</span> * write, flush, and close operations never block.<a name="line.23"></a>
<span class="sourceLineNo">024</span> * &lt;p/&gt;<a name="line.24"></a>
<span class="sourceLineNo">025</span> *<a name="line.25"></a>
<span class="sourceLineNo">026</span> * &lt;p&gt;<a name="line.26"></a>
<span class="sourceLineNo">027</span> * If the underlying output stream throws an {@link IOException} during any operation,<a name="line.27"></a>
<span class="sourceLineNo">028</span> * this instance will re-throw the exception for all subsequent operations.<a name="line.28"></a>
<span class="sourceLineNo">029</span> * &lt;/p&gt;<a name="line.29"></a>
<span class="sourceLineNo">030</span> *<a name="line.30"></a>
<span class="sourceLineNo">031</span> * &lt;p&gt;<a name="line.31"></a>
<span class="sourceLineNo">032</span> * Instances use an internal buffer whose size is configured at construction time;<a name="line.32"></a>
<span class="sourceLineNo">033</span> * if the buffer overflows, a {@link BufferOverflowException} is thrown. Alternately,<a name="line.33"></a>
<span class="sourceLineNo">034</span> * if a buffer size of zero is configured, the internal buffer will expand automatically as needed<a name="line.34"></a>
<span class="sourceLineNo">035</span> * (up to 2&lt;super&gt;31&lt;/super&gt; bytes).<a name="line.35"></a>
<span class="sourceLineNo">036</span> * However, this creates a memory leak if the underlying {@link OutputStream} blocks indefinitely.<a name="line.36"></a>
<span class="sourceLineNo">037</span> * &lt;/p&gt;<a name="line.37"></a>
<span class="sourceLineNo">038</span> *<a name="line.38"></a>
<span class="sourceLineNo">039</span> * &lt;p&gt;<a name="line.39"></a>
<span class="sourceLineNo">040</span> * Instances of this class are thread safe, and moreover writes are atomic: if multiple threads are writing<a name="line.40"></a>
<span class="sourceLineNo">041</span> * at the same time the bytes written in any single method invocation are written contiguously to the<a name="line.41"></a>
<span class="sourceLineNo">042</span> * underlying output.<a name="line.42"></a>
<span class="sourceLineNo">043</span> * &lt;/p&gt;<a name="line.43"></a>
<span class="sourceLineNo">044</span> */<a name="line.44"></a>
<span class="sourceLineNo">045</span>public class AsyncOutputStream extends FilterOutputStream {<a name="line.45"></a>
<span class="sourceLineNo">046</span><a name="line.46"></a>
<span class="sourceLineNo">047</span>    private static final AtomicInteger COUNTER = new AtomicInteger();<a name="line.47"></a>
<span class="sourceLineNo">048</span>    private static final int MIN_BUFFER_SIZE = 20;<a name="line.48"></a>
<span class="sourceLineNo">049</span>    private static final int MAX_BUFFER_SIZE = Integer.MAX_VALUE - 32;<a name="line.49"></a>
<span class="sourceLineNo">050</span><a name="line.50"></a>
<span class="sourceLineNo">051</span>    protected final Logger log = LoggerFactory.getLogger(getClass());<a name="line.51"></a>
<span class="sourceLineNo">052</span><a name="line.52"></a>
<span class="sourceLineNo">053</span>    private byte[] buf;                 // output buffer<a name="line.53"></a>
<span class="sourceLineNo">054</span>    private int count;                  // number of bytes in output buffer ready to be written<a name="line.54"></a>
<span class="sourceLineNo">055</span>    private int flushMark = -1;         // buffer byte at which a flush is requested, or -1 if none<a name="line.55"></a>
<span class="sourceLineNo">056</span>    private Thread thread;              // async writer thread<a name="line.56"></a>
<span class="sourceLineNo">057</span>    private IOException exception;      // exception caught by async thread<a name="line.57"></a>
<span class="sourceLineNo">058</span>    private boolean closed;             // this instance has been close()'d<a name="line.58"></a>
<span class="sourceLineNo">059</span>    private boolean expand;             // whether to auto-expand buffer as needed<a name="line.59"></a>
<span class="sourceLineNo">060</span><a name="line.60"></a>
<span class="sourceLineNo">061</span>    /**<a name="line.61"></a>
<span class="sourceLineNo">062</span>     * Convenience constructor for when an auto-expanding buffer is desired and a default thread name is to be used.<a name="line.62"></a>
<span class="sourceLineNo">063</span>     *<a name="line.63"></a>
<span class="sourceLineNo">064</span>     * @param out     underlying output stream<a name="line.64"></a>
<span class="sourceLineNo">065</span>     * @throws IllegalArgumentException if {@code out} is null<a name="line.65"></a>
<span class="sourceLineNo">066</span>     */<a name="line.66"></a>
<span class="sourceLineNo">067</span>    public AsyncOutputStream(OutputStream out) {<a name="line.67"></a>
<span class="sourceLineNo">068</span>        this(out, 0, AsyncOutputStream.class.getSimpleName() + "-" + AsyncOutputStream.COUNTER.incrementAndGet());<a name="line.68"></a>
<span class="sourceLineNo">069</span>    }<a name="line.69"></a>
<span class="sourceLineNo">070</span><a name="line.70"></a>
<span class="sourceLineNo">071</span>    /**<a name="line.71"></a>
<span class="sourceLineNo">072</span>     * Convenience constructor for when an auto-expanding buffer is desired.<a name="line.72"></a>
<span class="sourceLineNo">073</span>     *<a name="line.73"></a>
<span class="sourceLineNo">074</span>     * @param out     underlying output stream<a name="line.74"></a>
<span class="sourceLineNo">075</span>     * @param name    name for this instance; used to create the name of the background thread<a name="line.75"></a>
<span class="sourceLineNo">076</span>     * @throws IllegalArgumentException if {@code out} or {@code name} is null<a name="line.76"></a>
<span class="sourceLineNo">077</span>     */<a name="line.77"></a>
<span class="sourceLineNo">078</span>    public AsyncOutputStream(OutputStream out, String name) {<a name="line.78"></a>
<span class="sourceLineNo">079</span>        this(out, 0, name);<a name="line.79"></a>
<span class="sourceLineNo">080</span>    }<a name="line.80"></a>
<span class="sourceLineNo">081</span><a name="line.81"></a>
<span class="sourceLineNo">082</span>    /**<a name="line.82"></a>
<span class="sourceLineNo">083</span>     * Constructor.<a name="line.83"></a>
<span class="sourceLineNo">084</span>     *<a name="line.84"></a>
<span class="sourceLineNo">085</span>     * @param out     underlying output stream<a name="line.85"></a>
<span class="sourceLineNo">086</span>     * @param bufsize maximum number of bytes we can buffer, or zero for an auto-expanding buffer that has no fixed limit<a name="line.86"></a>
<span class="sourceLineNo">087</span>     * @param name    name for this instance; used to create the name of the background thread<a name="line.87"></a>
<span class="sourceLineNo">088</span>     * @throws IllegalArgumentException if {@code out} or {@code name} is null<a name="line.88"></a>
<span class="sourceLineNo">089</span>     * @throws IllegalArgumentException if {@code bufsize} is negative<a name="line.89"></a>
<span class="sourceLineNo">090</span>     */<a name="line.90"></a>
<span class="sourceLineNo">091</span>    public AsyncOutputStream(OutputStream out, int bufsize, String name) {<a name="line.91"></a>
<span class="sourceLineNo">092</span>        super(out);<a name="line.92"></a>
<span class="sourceLineNo">093</span>        if (out == null)<a name="line.93"></a>
<span class="sourceLineNo">094</span>            throw new IllegalArgumentException("null output");<a name="line.94"></a>
<span class="sourceLineNo">095</span>        if (name == null)<a name="line.95"></a>
<span class="sourceLineNo">096</span>            throw new IllegalArgumentException("null name");<a name="line.96"></a>
<span class="sourceLineNo">097</span>        if (bufsize &lt; 0)<a name="line.97"></a>
<span class="sourceLineNo">098</span>            throw new IllegalArgumentException("invalid bufsize " + bufsize);<a name="line.98"></a>
<span class="sourceLineNo">099</span>        this.expand = bufsize == 0;<a name="line.99"></a>
<span class="sourceLineNo">100</span>        this.buf = new byte[Math.min(bufsize, MIN_BUFFER_SIZE)];<a name="line.100"></a>
<span class="sourceLineNo">101</span><a name="line.101"></a>
<span class="sourceLineNo">102</span>        // Start worker thread<a name="line.102"></a>
<span class="sourceLineNo">103</span>        this.thread = new Thread(name) {<a name="line.103"></a>
<span class="sourceLineNo">104</span>            @Override<a name="line.104"></a>
<span class="sourceLineNo">105</span>            public void run() {<a name="line.105"></a>
<span class="sourceLineNo">106</span>                AsyncOutputStream.this.threadMain();<a name="line.106"></a>
<span class="sourceLineNo">107</span>            }<a name="line.107"></a>
<span class="sourceLineNo">108</span>        };<a name="line.108"></a>
<span class="sourceLineNo">109</span>        this.thread.setDaemon(true);<a name="line.109"></a>
<span class="sourceLineNo">110</span>        this.thread.start();<a name="line.110"></a>
<span class="sourceLineNo">111</span>        synchronized (this) { }<a name="line.111"></a>
<span class="sourceLineNo">112</span>    }<a name="line.112"></a>
<span class="sourceLineNo">113</span><a name="line.113"></a>
<span class="sourceLineNo">114</span>    /**<a name="line.114"></a>
<span class="sourceLineNo">115</span>     * Write data.<a name="line.115"></a>
<span class="sourceLineNo">116</span>     *<a name="line.116"></a>
<span class="sourceLineNo">117</span>     * &lt;p&gt;<a name="line.117"></a>
<span class="sourceLineNo">118</span>     * This method will never block. To effect a normal blocking write, use {@link #waitForSpace} first.<a name="line.118"></a>
<span class="sourceLineNo">119</span>     * &lt;/p&gt;<a name="line.119"></a>
<span class="sourceLineNo">120</span>     *<a name="line.120"></a>
<span class="sourceLineNo">121</span>     * @param b byte to write (lower 8 bits)<a name="line.121"></a>
<span class="sourceLineNo">122</span>     * @throws IOException             if an exception has been thrown by the underlying stream<a name="line.122"></a>
<span class="sourceLineNo">123</span>     * @throws IOException             if this instance has been closed<a name="line.123"></a>
<span class="sourceLineNo">124</span>     * @throws BufferOverflowException if the buffer does not have room for the new byte<a name="line.124"></a>
<span class="sourceLineNo">125</span>     */<a name="line.125"></a>
<span class="sourceLineNo">126</span>    @Override<a name="line.126"></a>
<span class="sourceLineNo">127</span>    public void write(int b) throws IOException {<a name="line.127"></a>
<span class="sourceLineNo">128</span>        this.write(new byte[] { (byte)b }, 0, 1);<a name="line.128"></a>
<span class="sourceLineNo">129</span>    }<a name="line.129"></a>
<span class="sourceLineNo">130</span><a name="line.130"></a>
<span class="sourceLineNo">131</span>    /**<a name="line.131"></a>
<span class="sourceLineNo">132</span>     * Write data.<a name="line.132"></a>
<span class="sourceLineNo">133</span>     *<a name="line.133"></a>
<span class="sourceLineNo">134</span>     * &lt;p&gt;<a name="line.134"></a>
<span class="sourceLineNo">135</span>     * This method will never block. To effect a normal blocking write, invoke {@link #waitForSpace} first.<a name="line.135"></a>
<span class="sourceLineNo">136</span>     * &lt;/p&gt;<a name="line.136"></a>
<span class="sourceLineNo">137</span>     *<a name="line.137"></a>
<span class="sourceLineNo">138</span>     * @param data bytes to write<a name="line.138"></a>
<span class="sourceLineNo">139</span>     * @param off  starting offset in buffer<a name="line.139"></a>
<span class="sourceLineNo">140</span>     * @param len  number of bytes to write<a name="line.140"></a>
<span class="sourceLineNo">141</span>     * @throws IOException              if an exception has been thrown by the underlying stream<a name="line.141"></a>
<span class="sourceLineNo">142</span>     * @throws IOException              if this instance has been closed<a name="line.142"></a>
<span class="sourceLineNo">143</span>     * @throws BufferOverflowException  if the buffer does not have room for the new data<a name="line.143"></a>
<span class="sourceLineNo">144</span>     * @throws IllegalArgumentException if {@code len} is negative<a name="line.144"></a>
<span class="sourceLineNo">145</span>     */<a name="line.145"></a>
<span class="sourceLineNo">146</span>    @Override<a name="line.146"></a>
<span class="sourceLineNo">147</span>    public synchronized void write(byte[] data, int off, int len) throws IOException {<a name="line.147"></a>
<span class="sourceLineNo">148</span><a name="line.148"></a>
<span class="sourceLineNo">149</span>        // Check exception conditions<a name="line.149"></a>
<span class="sourceLineNo">150</span>        this.checkExceptions();<a name="line.150"></a>
<span class="sourceLineNo">151</span>        if (len &lt; 0)<a name="line.151"></a>
<span class="sourceLineNo">152</span>            throw new IllegalArgumentException("len = " + len);<a name="line.152"></a>
<span class="sourceLineNo">153</span>        if (len == 0)<a name="line.153"></a>
<span class="sourceLineNo">154</span>            return;<a name="line.154"></a>
<span class="sourceLineNo">155</span>        if (this.count + len &gt; this.buf.length) {<a name="line.155"></a>
<span class="sourceLineNo">156</span>            if (!this.expand) {<a name="line.156"></a>
<span class="sourceLineNo">157</span>                throw new BufferOverflowException(this.count + " + " + len + " = " + (this.count + len)<a name="line.157"></a>
<span class="sourceLineNo">158</span>                  + " byte(s) would exceed the " + this.buf.length + " byte buffer");<a name="line.158"></a>
<span class="sourceLineNo">159</span>            }<a name="line.159"></a>
<span class="sourceLineNo">160</span>            this.resizeBuffer(Math.max(this.count + len, this.buf.length * 2));<a name="line.160"></a>
<span class="sourceLineNo">161</span><a name="line.161"></a>
<span class="sourceLineNo">162</span>            final byte[] newBuf = new byte[Math.max(this.count + len, this.buf.length * 2)];<a name="line.162"></a>
<span class="sourceLineNo">163</span>            System.arraycopy(this.buf, 0, newBuf, 0, this.count);<a name="line.163"></a>
<span class="sourceLineNo">164</span>            this.buf = newBuf;<a name="line.164"></a>
<span class="sourceLineNo">165</span>        }<a name="line.165"></a>
<span class="sourceLineNo">166</span><a name="line.166"></a>
<span class="sourceLineNo">167</span>        // Add data to buffer<a name="line.167"></a>
<span class="sourceLineNo">168</span>        System.arraycopy(data, off, this.buf, this.count, len);<a name="line.168"></a>
<span class="sourceLineNo">169</span>        this.count += len;<a name="line.169"></a>
<span class="sourceLineNo">170</span><a name="line.170"></a>
<span class="sourceLineNo">171</span>        // Wakeup writer thread<a name="line.171"></a>
<span class="sourceLineNo">172</span>        this.notifyAll();<a name="line.172"></a>
<span class="sourceLineNo">173</span>    }<a name="line.173"></a>
<span class="sourceLineNo">174</span><a name="line.174"></a>
<span class="sourceLineNo">175</span>    /**<a name="line.175"></a>
<span class="sourceLineNo">176</span>     * Flush output. This method will cause the underlying stream to be flushed once all of the data written to this<a name="line.176"></a>
<span class="sourceLineNo">177</span>     * instance at the time this method is invoked has been written to it.<a name="line.177"></a>
<span class="sourceLineNo">178</span>     *<a name="line.178"></a>
<span class="sourceLineNo">179</span>     * &lt;p&gt;<a name="line.179"></a>
<span class="sourceLineNo">180</span>     * If additional data is written and then a second flush is requested before the first flush has actually occurred,<a name="line.180"></a>
<span class="sourceLineNo">181</span>     * the first flush will be canceled and only the second flush will be applied. Normally this is not a problem because<a name="line.181"></a>
<span class="sourceLineNo">182</span>     * the act of writing more data and then flushing forces earlier data to be flushed as well.<a name="line.182"></a>
<span class="sourceLineNo">183</span>     * &lt;/p&gt;<a name="line.183"></a>
<span class="sourceLineNo">184</span>     *<a name="line.184"></a>
<span class="sourceLineNo">185</span>     * &lt;p&gt;<a name="line.185"></a>
<span class="sourceLineNo">186</span>     * This method will never block. To block until the underlying flush operation completes, invoke {@link #waitForIdle}.<a name="line.186"></a>
<span class="sourceLineNo">187</span>     * &lt;/p&gt;<a name="line.187"></a>
<span class="sourceLineNo">188</span>     *<a name="line.188"></a>
<span class="sourceLineNo">189</span>     * @throws IOException if this instance has been closed<a name="line.189"></a>
<span class="sourceLineNo">190</span>     * @throws IOException if an exception has been detected on the underlying stream<a name="line.190"></a>
<span class="sourceLineNo">191</span>     * @throws IOException if the current thread is interrupted; the nested exception will an {@link InterruptedException}<a name="line.191"></a>
<span class="sourceLineNo">192</span>     */<a name="line.192"></a>
<span class="sourceLineNo">193</span>    @Override<a name="line.193"></a>
<span class="sourceLineNo">194</span>    public synchronized void flush() throws IOException {<a name="line.194"></a>
<span class="sourceLineNo">195</span>        this.checkExceptions();<a name="line.195"></a>
<span class="sourceLineNo">196</span>        this.flushMark = this.count;<a name="line.196"></a>
<span class="sourceLineNo">197</span>        this.notifyAll();                               // wake up writer thread<a name="line.197"></a>
<span class="sourceLineNo">198</span>    }<a name="line.198"></a>
<span class="sourceLineNo">199</span><a name="line.199"></a>
<span class="sourceLineNo">200</span>    /**<a name="line.200"></a>
<span class="sourceLineNo">201</span>     * Close this instance. This will (eventually) close the underlying output stream.<a name="line.201"></a>
<span class="sourceLineNo">202</span>     *<a name="line.202"></a>
<span class="sourceLineNo">203</span>     * &lt;p&gt;<a name="line.203"></a>
<span class="sourceLineNo">204</span>     * If this instance has already been closed, nothing happens.<a name="line.204"></a>
<span class="sourceLineNo">205</span>     * &lt;/p&gt;<a name="line.205"></a>
<span class="sourceLineNo">206</span>     *<a name="line.206"></a>
<span class="sourceLineNo">207</span>     * &lt;p&gt;<a name="line.207"></a>
<span class="sourceLineNo">208</span>     * This method will never block. To block until the underlying close operation completes, invoke {@link #waitForIdle}.<a name="line.208"></a>
<span class="sourceLineNo">209</span>     * &lt;/p&gt;<a name="line.209"></a>
<span class="sourceLineNo">210</span>     *<a name="line.210"></a>
<span class="sourceLineNo">211</span>     * @throws IOException if an exception has been detected on the underlying stream<a name="line.211"></a>
<span class="sourceLineNo">212</span>     */<a name="line.212"></a>
<span class="sourceLineNo">213</span>    @Override<a name="line.213"></a>
<span class="sourceLineNo">214</span>    public synchronized void close() throws IOException {<a name="line.214"></a>
<span class="sourceLineNo">215</span>        if (this.closed)<a name="line.215"></a>
<span class="sourceLineNo">216</span>            return;<a name="line.216"></a>
<span class="sourceLineNo">217</span>        this.closed = true;<a name="line.217"></a>
<span class="sourceLineNo">218</span>        this.notifyAll();                               // wake up writer thread<a name="line.218"></a>
<span class="sourceLineNo">219</span>    }<a name="line.219"></a>
<span class="sourceLineNo">220</span><a name="line.220"></a>
<span class="sourceLineNo">221</span>    /**<a name="line.221"></a>
<span class="sourceLineNo">222</span>     * Get the exception thrown by the underlying output stream, if any.<a name="line.222"></a>
<span class="sourceLineNo">223</span>     *<a name="line.223"></a>
<span class="sourceLineNo">224</span>     * @return thrown exception, or {@code null} if none has been thrown by the underlying stream<a name="line.224"></a>
<span class="sourceLineNo">225</span>     */<a name="line.225"></a>
<span class="sourceLineNo">226</span>    public synchronized IOException getException() {<a name="line.226"></a>
<span class="sourceLineNo">227</span>        return this.exception;<a name="line.227"></a>
<span class="sourceLineNo">228</span>    }<a name="line.228"></a>
<span class="sourceLineNo">229</span><a name="line.229"></a>
<span class="sourceLineNo">230</span>    /**<a name="line.230"></a>
<span class="sourceLineNo">231</span>     * Get the capacity of this instance's output buffer.<a name="line.231"></a>
<span class="sourceLineNo">232</span>     *<a name="line.232"></a>
<span class="sourceLineNo">233</span>     * &lt;p&gt;<a name="line.233"></a>
<span class="sourceLineNo">234</span>     * If a (fixed) non-zero value was given at construction time, this will return that value.<a name="line.234"></a>
<span class="sourceLineNo">235</span>     * &lt;/p&gt;<a name="line.235"></a>
<span class="sourceLineNo">236</span>     *<a name="line.236"></a>
<span class="sourceLineNo">237</span>     * @return current output buffer capacity<a name="line.237"></a>
<span class="sourceLineNo">238</span>     */<a name="line.238"></a>
<span class="sourceLineNo">239</span>    public synchronized int getBufferSize() {<a name="line.239"></a>
<span class="sourceLineNo">240</span>        return this.buf.length;<a name="line.240"></a>
<span class="sourceLineNo">241</span>    }<a name="line.241"></a>
<span class="sourceLineNo">242</span><a name="line.242"></a>
<span class="sourceLineNo">243</span>    /**<a name="line.243"></a>
<span class="sourceLineNo">244</span>     * Get the number of free bytes remaining in the output buffer.<a name="line.244"></a>
<span class="sourceLineNo">245</span>     *<a name="line.245"></a>
<span class="sourceLineNo">246</span>     * @return current number of available bytes in the output buffer<a name="line.246"></a>
<span class="sourceLineNo">247</span>     * @throws IOException              if this instance is or has been closed<a name="line.247"></a>
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<span class="sourceLineNo">260</span>     * @throws IOException              if this instance is or has been closed<a name="line.260"></a>
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<span class="sourceLineNo">272</span>     * &lt;p&gt;<a name="line.272"></a>
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<span class="sourceLineNo">280</span>     * @throws IOException              if this instance is or has been closed<a name="line.280"></a>
<span class="sourceLineNo">281</span>     * @throws IOException              if an exception has been detected on the underlying stream<a name="line.281"></a>
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<span class="sourceLineNo">283</span>     * @throws IllegalArgumentException if {@code timeout} is negative<a name="line.283"></a>
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<span class="sourceLineNo">301</span>     * Wait for all outstanding work to complete.<a name="line.301"></a>
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<span class="sourceLineNo">305</span>     * @throws IOException              if this instance is or has been closed<a name="line.305"></a>
<span class="sourceLineNo">306</span>     * @throws IOException              if an exception has been detected on the underlying stream<a name="line.306"></a>
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<span class="sourceLineNo">321</span>     * Check for exceptions.<a name="line.321"></a>
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<span class="sourceLineNo">323</span>     * @throws IOException if this instance has been closed<a name="line.323"></a>
<span class="sourceLineNo">324</span>     * @throws IOException if an exception has been detected on the underlying stream<a name="line.324"></a>
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<span class="sourceLineNo">333</span>    /**<a name="line.333"></a>
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<span class="sourceLineNo">454</span>                    return predicate.test();<a name="line.454"></a>
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<span class="sourceLineNo">456</span>            });<a name="line.456"></a>
<span class="sourceLineNo">457</span>        } catch (CheckedExceptionWrapper e) {<a name="line.457"></a>
<span class="sourceLineNo">458</span>            throw (IOException)e.getException();<a name="line.458"></a>
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<span class="sourceLineNo">460</span>    }<a name="line.460"></a>
<span class="sourceLineNo">461</span>}<a name="line.461"></a>
<span class="sourceLineNo">462</span><a name="line.462"></a>




























































</pre>
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